diff options
| author |   Markos Chandras <markos.chandras@imgtec.com> | 2014-07-14 12:46:13 +0100 |
|---|---|---|
| committer |   Ralf Baechle <ralf@linux-mips.org> | 2014-08-02 00:06:39 +0200 |
| commit | 3d528b326d7da8e28ec62c2ff1a92e85d93af098 (patch) | |
| tree | bb56b98d03cbf33c0f07f6d3c3e3234101eb11f1 /arch/mips | |
| parent | MIPS: asm: Add register definitions for Hardware Table Walker (diff) | |
| download | linux-dev-3d528b326d7da8e28ec62c2ff1a92e85d93af098.tar.xz linux-dev-3d528b326d7da8e28ec62c2ff1a92e85d93af098.zip | |
MIPS: kernel: cpu-probe: Add support for the HardWare Table Walker
Detect if the core implements the HTW and set the option accordingly.
Also, add a new kernel parameter called 'nohtw' allowing
the user to disable the htw support and fallback to the software
refill handler.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7335/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/kernel/cpu-probe.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c index 2d2e2877b1ea..0d30433db54b 100644 --- a/arch/mips/kernel/cpu-probe.c +++ b/arch/mips/kernel/cpu-probe.c @@ -54,6 +54,20 @@ static int __init dsp_disable(char *s) __setup("nodsp", dsp_disable); +static int mips_htw_disabled; + +static int __init htw_disable(char *s) +{ + mips_htw_disabled = 1; + cpu_data[0].options &= ~MIPS_CPU_HTW; + write_c0_pwctl(read_c0_pwctl() & + ~(1 << MIPS_PWCTL_PWEN_SHIFT)); + + return 1; +} + +__setup("nohtw", htw_disable); + static inline void check_errata(void) { struct cpuinfo_mips *c = ¤t_cpu_data; @@ -321,6 +335,9 @@ static inline unsigned int decode_config3(struct cpuinfo_mips *c) c->options |= MIPS_CPU_SEGMENTS; if (config3 & MIPS_CONF3_MSA) c->ases |= MIPS_ASE_MSA; + /* Only tested on 32-bit cores */ + if ((config3 & MIPS_CONF3_PW) && config_enabled(CONFIG_32BIT)) + c->options |= MIPS_CPU_HTW; return config3 & MIPS_CONF_M; } @@ -1193,6 +1210,12 @@ void cpu_probe(void) if (mips_dsp_disabled) c->ases &= ~(MIPS_ASE_DSP | MIPS_ASE_DSP2P); + if (mips_htw_disabled) { + c->options &= ~MIPS_CPU_HTW; + write_c0_pwctl(read_c0_pwctl() & + ~(1 << MIPS_PWCTL_PWEN_SHIFT)); + } + if (c->options & MIPS_CPU_FPU) { c->fpu_id = cpu_get_fpu_id(); |